I have a 2000 5281 BMW, when I put on brakes it pulsates sometimes, what is this, add about 4 months ago I had the rotors maintance.

If the brake pedal pulsates while high speed braking, the rotors are warped/out of round. This can also produce noise as it can cause the caliper to move back and forth. You either have poor quality/cheap parts installed or the parts were installed with improper lube on the slide assemblies and there is dirt/rust causing the pins not to move freely or the pad shims are old and rusted causing the pads to stick and overheat the rotors. Have the brakes inspected for the source of the problem

HI if you have pulsation after a month you must replace the rotors
they are too thin and the heat is warping them faster then before you
had them turned
note you replace brake pads and rotors

good luck

Pulsating brakes are often caused by warped brake rotors. In order to check for a brake that isn't releasing I would suggest lifting one wheel at a time, applying the brakes and immediately checking if that wheel turns freely. Repeat on all 4 wheels. If you find one that isn't turning freely you'll have to address the problem with that brake.

check rotor and brake pads. also check fluid level. one of those 3 causing problems.
more and likely its the rotor. its cheaper to buy new ones for around 20-30 dollars.
warped rotor will cause the pedal to ..pulsate. and more and likely you pads are wore.
when getting new rotor always put new shoes on so the rotor it can wear evenly.

Check this procedure...
1. Check wheel lug nut torque and tighten evenly to specification.
2. Check the brake rotor for trueness and thickness variations. Replace the rotor if it is too thin, warped, or if the thickness varies beyond specification. Some rotors can be machined; consult the manufacturer's specifications and recommendations before using a machined brake rotor.
3. Check the brake caliper or caliper bracket mounting bolt torque and inspect for looseness. Torque the mounting bolts and inspect for wear or any looseness, including worn mounting brackets, bushings and sliding pins.
4. Check the wheel bearing for looseness. If the bearing is loose, adjust if possible, otherwise replace the bearing.

Before Removing the Brake Rotor from the vehicle it should be tested for warpage.

Use a Dial Indicator for checking to see if the rotor is warped. Anything over .003 can be felt as pulsation in the foot pedal as it double when you add the other side of the rotor and then add the opposite rotor. Replace rotor If it reads over .003

Keep us updated.

It is an ABS issue.

Good luck.

if you had brakes and rotors 6 months ago,did you do just front or just rear?
if you did front and squeal is in front,the new pads got hot and it glazed them,but the rotors are you pulsating pedal,are you sure they did rotors and pads?
there is no way this should be happening in 6 months.

The pulsating sounds like rotors warped from overheating. As far as light goes, may be float or sensor at master cylinder faulty & making light trip.

Your brake rotors may be warped, which causes the pulsating you are experiencing. It's ok to drive it like this (although annoying), so if it is driving you crazy, you can have the rotors 'turned' (ground down to eliminate any high spots) or just replace them with new rotors. An automotive shop/parts store needs to measure the thickness of the rotors to determine if the rotors are thick enough to allow them to be turned. Check the price on new ones anyway, as sometimes the price difference is minimal.

Well even though you had the rotors turned, they still could be warped and causing the car to shake at a high rate of speed when the brakes are applied. My suggestion is to replace the rotors asap.